Development of Passive Fire Protection Mortars

  Ci a ion: Cae ano, H.; Laím, L.; San iago, A.; Du ães, L.; Shahbazian, A. De elopmen o Passi e Fi e P o ec ion Mo a s. Appl. Sci. 2022, 12, 2093. h ps://doi.o g/10.3390/ app12042093 Academic Edi o : Sang-Hyo Kim Recei ed: 23 Decembe 2021 Accep ed: 7 Feb ua y 2022 Published: 17 Feb ua y 2022 Publishe ’s No e: MDPI s ays neu al wi h ega d o ju isdic ional claims in published maps and ins i u ional a il- ia ions. Copy igh : © 2022 by he au ho s. Licensee MDPI, Basel, Swi ze land. This a icle is an open access a icle dis ibu ed unde he e ms and condi ions o he C ea i e Commons A ibu ion (CC BY) license (h ps:// c ea i ecommons.o g/licenses/by/ 4.0/). applied sciences A icle De elopmen o Passi e Fi e P o ec ion Mo a s Hugo Cae ano 1,* , Luís Laím1, Aldina San iago 1, Luísa Du ães 2and Ashkan Shahbazian 1 1Depa men o Ci il Enginee ing, Uni e si y o Coimb a, ISISE, Rua Luís Reis San os, 3030-790 Coimb a, Po ugal; [email p o ec ed] (L.L.); [email p o ec ed] (A.S.); [email p o ec ed] (A.S.) 2Depa men o Chemical Enginee ing, Uni e si y o Coimb a, CIEPQPF, Rua Síl io Lima, 3030-790 Coimb a, Po ugal; [email p o ec ed] *Co espondence: [email p o ec ed]; Tel.:+00351-239-797-261 Abs ac : Du ing a i e e en , he s abili y o s eel s uc u es may be comp omised, and s uc u al collapse may occu due o he loss o hei mechanical esis ance as he empe a u e inc eases. One o he solu ions o educe his p oblem is he p o ec ion wi h a coa ing using enhanced i e- esis an mo a s. This pape epo s a de ailed expe imen al wo k aiming o de elop gypsum and cemen - based mo a s o passi e i e p o ec ion and e alua e hei composi ion’s e ec in he inal he mal pe o mance. Two ypes o specimens we e es ed: (i) small specimens composed o a mo a coa ing (10 mm hick) and one s eel pla e and (ii) squa e sec ion sho ubula s eel columns wi h 20 mm o coa ing. The e alua ion o he he mal p o ec ion was ca ied ou by (a) measu ing he he mal g adien be ween he exposed su ace o he p o ec ed s eel pla e unde high empe a u es and he mo a -s eel in e ace and (b) assessing he i e esis ance o he sho s eel columns. I was concluded ha he composi ions wi h gypsum binde p esen be e he mal insula ion han he cemen i ious composi ions. Addi ionally, he in oduc ion o nano- and mic opa icles o silica s ill sligh ly imp o ed he he mal insula ion o he es ed composi ions. Keywo ds: s eel columns; nano- and mic osilica; gypsum; cemen ; mo a ; passi e i e p o ec ion; insula ion; i e; hea ans e 1. In oduc ion The e is a g owing in e es in de eloping al e na i e and sus ainable cons uc ion ma e ials wi h enhanced p ope ies. As me als a e in ini ely ecyclable, his ype o con- s uc ion is pa o a u u e o “g een cons uc ion”, hus con ibu ing o a sec o o he economy wi h low en i onmen al impac [1–3]. Howe e , s eel s uc u es show some weaknesses, especially hei s uc u al beha iou when subjec ed o i e [ 4 – 9 ]. Due o he high he mal conduc i i y o he s eel, he high sec ion ac o o he membe s, and he apid deg ada ion o he s eel mechanical p ope - ies, wi h he inc ease o s eel empe a u e, apid change in he s i ness and mechanical esis ance may be no iced in he s uc u e. I s esis ance and s abili y may be comp omised, leading o he collapse o some elemen s o e en o he en i e s uc u e [10–15]. The he mal p o ec ion o hese s uc u al elemen s is c ucial. The i e p o ec ion o s uc u es can be achie ed by combining ac i e and passi e i e p o ec ion sys ems and managemen sys ems (smoke exhaus sys ems, communica ion and e acua ion p ocedu es, i e de ec ion sys ems, and compa men a ion [ 16 ]). Ac i e i e p o ec ion can consis o sys ems o i ems such as i e ex inguishe s, s andpipes, sp inkle sys ems, and i e blan- ke s [ 17 ]. I is equi ed ha hese sys ems ha e a quick esponse capaci y in ex inguishing o con olling he de elopmen o a i e in i s ini ial phase [ 18 ]. Howe e , implemen ing hese sys ems has high ins alla ion and main enance cos s, and hei esul s can ha e low unc ional eliabili y and unsa is ac o y ope a ional esul s [19]. Appl. Sci. 2022,12, 2093. h ps://doi.o g/10.3390/app12042093 h ps://www.mdpi.com/jou nal/applsci Appl. Sci. 2022,12, 2093 2 o 20 In u n, when applying passi e p o ec ion, i is almos su e ha i will be ope a ional du ing a i e e en . Passi e sys ems include he i e esis ance o s uc u al o nons uc- u al membe s o a building, such as columns, beams, walls, and ceilings. This pu pose ensu es adequa e e acua ion imes, minimum sa e y condi ions o i e igh ing and escue ope a ions and minimises p ope y, economic, and li e losses [20]. The mos common me hod o p o ec a membe om exposu e o ex eme empe a- u es is o apply insula ion ma e ials a ound he s uc u al membe s. Insula ion ma e ials used as i e p o ec ion in s uc u al s eel membe s can be: boa d sys ems (gypsum boa d o calcium silica e), insula ing blanke s (ce amic, ock, and glass wool), sp ay sys ems, o in umescen coa ings [ 21 ]. These ma e ials should be cheape han he s eelwo k, easy o applica ion, sa e (i.e., no be haza dous du ing he applica ion and in se ice, o oxic in he e en o i e), and should insula e and emain undamaged du ing he i e a ack (wi h limi ed de achmen s and ac u es du ing he equi ed i e esis ance) [22]. One solu ion ha mee s hese p o ec ion equi emen s is he coa ing wi h enhanced i e- esis an mo a s due o he in oduc ion o nanosilica pa icles and he mally s able and po ous agg ega es [ 23 ]. Wi h he eme gence o nanoma e ials (silica nanopa icles, i anium dioxide nanopa icles, alumina nanopa icles, and ca bon nano ubes, e c.), hei inco po a ion in pas es, mo a s, and o he cemen -based ma e ials has appea ed as a possibili y o imp o e hei mechanical and he mal p ope ies: highe du abili y, be e esis ance o co osion and be e i e esis ance [ 24 – 28 ], wi h he silica nanopa icles being he mos s udied nanoma e ial in cemen [ 26 ]. Howe e , li le a en ion has been gi en o o he p ope ies, such as he mal conduc i i y a ele a ed empe a u es [29]. When subjec ed o high empe a u es, pe li e and e miculi e ha e been inco po a ed in cemen mo a s o imp o e hei he mal pe o mance [ 30 ]. Pe li e consis s o a siliceous olcanic ock wi h 2% o 6% wa e combined. Howe e , when small pe li e g ains a e subjec ed o high empe a u es (870 ◦ C), hey s ongly inc ease hei olume wi h nume ous iny, sealed ai cells, like popco n gi ing ise o ligh weigh expanded pe li e. Ligh weigh expanded pe li e has low he mal conduc i i y (0.04–0.06 W/mK), ela i ely high mel ing poin (1260–1343 ◦ C) and low densi y (loose: 50–400 kg/m 3 ) [ 31 ]. These cha ac e is ics make pe li e a ma e ial wi h excellen insula ing p ope ies. Ve miculi e consis s o a micalike mine al con aining a shiny lake ( he phyllosilica e g oup). I is p oduced a ambien condi ions om he wea he ing/hyd o he mal al e a ion o phlogopi e o bio i e [ 30 ]. Simila o pe li e, when e miculi e pa icles a e subjec ed o high empe a u es ( om 650 o 950 ◦ C), hey expand, p esen ing a densi y o 80 o 120 kg/m3, a mel ing poin be ween 1240 o 1430 ◦ C and a he mal conduc i i y be ween 0.04 o 0.12 W/mK [ 32 ]. Mo eo e , due o hei highly po ous s uc u e, hese ma e ials abso b mois u e in a ying deg ees (depending on hei ype), which when combined wi h he low he mal conduc i i y, ex ends hei du abili y du ing he i e. Pe li e may be a be e supplemen han e miculi e, no only due o i s he mal conduc i i y bu also o he high e ac ion e ec o e miculi e [ 33 ]. As hey a e ma e ials wi h good he mal p ope ies, hey can be used in he de elopmen o plas e o cemen mo a s as a passi e i e p o ec ion solu ion in s eel s uc u es. In addi ion o cemen , plas e can also be used as a binde and combined wi h pe li e and/o e miculi e o de elop mo a s o passi e i e p o ec ion. Compa ed o cemen , gypsum is much cheape , easie o p oduce, and p o ides a mo e e ec i e he mal ba ie because i has a lowe he mal conduc i i y han cemen . I also con ibu es o he ene gy loss om i e due o i s endo he mic dehyd a ion p ocess [34,35]. S udies ha e shown ha pe li e–Po land cemen and pe li e–gypsum coa ings a e he mos e ec i e plas e s as i e ba ie s and in e a ding he conduc ion o high empe a u es ac oss hei hickness among di e en kinds o coa ings, such as adi ional-cemen plas e , e miculi e cemen /gypsum-based mo a , in umescen coa ing, calcium silica e boa d, and LECA-cemen plas e [36–38]. The e o e, his pape p esen s he de elopmen o di e en gypsum o cemen -based mo a s as passi e i e p o ec ion ma e ials, he e alua ion o he in luence o agg ega e Appl. Sci. 2022,12, 2093 3 o 20 size, and he addi ion o silica mic o- and nanopa icles on hei he mal pe o mance and assessmen o i e esis ance o he p o ec ed sho s eel columns. 2. Ma e ials and Me hods 2.1. Ma e ials and Composi ions In a p elimina y phase, se e al mo a s based on cemen o gypsum we e de eloped, wi h di e en dosages o aw ma e ials, acco ding o he s a e o he a as p esen ed in he in oduc ion o his pape (Table 1). The ollowing ma e ials we e used in he composi ions o he mo a s: comme cial passi e p o ec ion solu ions 1 (IGN) and 2 (VER), Po land cemen CEM II/B-L 32.5 (PC), Isidac 40 e ac o y cemen (IRC), Topeca M40 e ac o y cemen (TRC), Ele oland e ac o y cemen (ERC), gypsum powde (GP), expanded e miculi e wi h dimensions be ween 0.5 and 3 mm (EV), expanded pe li e wi h dimensions be ween 1 and 5 mm (EP), polyp opylene ibe s wi h an a e age diame e o 31 µ m and an a e age leng h o 6 mm (PP), silica sand wi h dimensions be ween 0.01 and 2.00 mm (SS), expanded clay wi h dimensions be ween 0.01 and 2.00 mm (EC), silica mic opa icles wi h an a e age diame e o 1000 nm (MS), silica nanopa icles wi h an a e age diame e o 200 nm (NS), and wa e (W). Silica mic o- and nanopa icles we e syn hesised in he labo a o y, acco ding o he p ocedu e desc ibed by Vaz-Ramos e al. [ 15 ]. Table 1. Mo a composi ions de eloped a LEMEC (a) (amoun o ma e ials in olume %). Mo a Designa ion Binde s Type CPPS Agg ega es NS and MS W/B PC ERC IRC TRC GP IGN VER SS EV EP EC PP/B C_1 30% - - - - - - 70% - - - - - 0.50 C_2 29% - - - - - - 70% - - - 1% - 0.50 C_3 28% - - - - - - 70% - - - 1% 1% 0.50 C_4 26% - - - - - - 70% - - - 1% 3% 0.50 C_5 23% - - - - - - 70% - - - 1% 6% 0.50 C_6 29% - - - - - - - - 70% - 1% - 0.50 C_7 29% - - - - - - 35% 35% - - 1% - 0.50 C_8 29% - - - - - - - - - 70% 1% - 0.50 C_9 - 30% - - - - - 70% - - - - - 0.50 C_10 - 29% - - - - - 70% - - - 1% - 0.70 C_11 - 29% - - - - - - - 70% - 1% - 0.70 C_12 - 29% - - - - - 35% 35% - - 1% - 0.70 C_13 - - 30% - - - - 70% - - - - - 0.50 C_14 - - 29% - - - - 70% - - - 1% - 0.70 C_15 - - 29% - - - - - - 70% - 1% - 0.70 C_16 - - 29% - - - - 35% 35% - - 1% - 0.70 C_17 - - - - - 100% - - - - - - - 0.50 C_18 - - - - - 100% - - - - - - - 0.60 C_19 - - - - - 99% - - - - - 1% - 0.70 C_20 - - - 100% - - - - - - - - - 0.50 C_21 - - - 100% - - - - - - - - - 0.70 C_22 - - - 99% - - - - - - - 1% - 0.70 C_23 - - - - - 80% - - 20% - - - - 0.70 C_24 - - - - - 99% - - - - - 1% - 0.70 C_25 - - - - - - 100% - - - - - - 0.50 C_26 - - - - - - 100% - - - - - - 0,60 C_27 - - - - - - 100% - - - - - - 0.70 C_28 - - - - - - 99% - - - - 1% - 0.60 C_29 49% - - - - - - - - 50% - 1% - 1.30 C_30 49% - - - - - - - 50% - - 1% - 3.21 C_31 50% - - - - - - - 25% 25% - - - 2.17 C_32 49% - - - - - - - 25% 25% - 1% - 2.17 C_33 - - - - 100% - - - - - - - - 0.50 C_34 - - - - 100% - - - - - - - - 0.50 C_35 - - - - 100% - - - - - - - - 0.60 C_36 - - - - 40% - - - - 60% - - - 1.25 C_37 - - - - 50% - - - - 50% - - - 1.00 C_38 - - - - 60% - - - - 40% - - - 0.83 C_39 - - - - 40% - - - 60% - - - - 2.10 C_40 - - - - 50% - - - 50% - - - - 1.60 C_41 - - - - 60% - - - 40% - - - - 1.25 C_42 - - - - 20% - - - 40% 40% - - - 3.75 C_43 - - - - 30% - - - 35% 35% - - - 2.50 C_44 - - - - 40% - - - 30% 30% - - - 2.15 C_45 - - - - 99.5% - - - - - - 0.5% - 0.50 C_46 - - - - 99% - - - - - - 1% - 0.50 C_47 - - - - 98.5% - - - - - - 1.5% - 0.50 C_48 - 20% - - - - - - 40% 40% - - - 2.75 (a) Labo a o y o Tes ing Ma e ials and S uc u es o Uni e si y o Coimb a. Appl. Sci. 2022,12, 2093 4 o 20 Tes ing wo comme cial passi e p o ec ion solu ions es ed, i was possible o iden i y he comme cial solu ion ha p o ided one o he bes he mal insula ion esul s, which came o be conside ed as he e e ence mo a (CM). F om he p elimina y es s phase, ou di e en mo a s we e selec ed (DCM, DGMP, DGMV, and DRCM) om o y di e en mo a s de eloped wi h g ea e he mal insula ion capaci y han ha p o ided by he e e ence mo a . As can be seen in Table 2, he DCM was made wi h Po land cemen , e miculi e and polyp opylene ibe s, he DGMP was p epa ed gypsum and pe li e, he DGMV was made o gypsum and e miculi e and he DRCM was p epa ed wi h e ac o y cemen , pe li e, and e miculi e. Table 2. Cons i u ion o each selec ed mo a (amoun o ma e ials in olume %). Mo a Designa ion CPPS PC RC GP EV EP PP/B W/B CM 100% - - - - - - 0.60 * DCM - 49% - - 50% - 1% 3.21 DGMP - - - 40% - 60% - 1.21 DGMV - - - 50% 50% - - 2.10 DRCM - - 50% - 25% 25% - 2.75 * Wa e comme cial solu ion a io in weigh %. To analyze he in luence o expanded pe li e and expanded e miculi e g ain size on he he mal pe o mance o labo a o y de eloped mo a s, wo di e en g inding me hods we e used: Los Angeles (LA) and Indus ial Mill (IM). The i s me hod was ca ied ou using he Los Angeles me hod, which agmen ed he agg ega e by ab asion and shock using s eel balls. The pa icle size o hese aw ma e ials was assessed using a pa icle size analysis (speci ica ion LNEC E 195-1966), and i was obse ed ha hei size anged om 0.075 o 0.85 mm. The second me hod was ca ied ou using an indus ial mill, which by he ic ion o he agg ega e wi h he d um signi ican ly educed he size o i s pa icles compa ed o he LA me hod. The pa icle size analysis iden i ied a pa icle size anging om 0.025 o 0.40 mm. Finally, di e en dosages o silica mic o and nanopa icles we e added and es ed in DCM, DGMP, DGMV, and DRCM o assess hei in luence on he he mal insula ion o he espec i e mo a s, as desc ibed in he ollowing sec ion o he pape . 2.2. Expe imen al P og am The expe imen al p og am included wo di e en ypes o es s, depending on he ype o specimens: s eel pla e (SP) (Table 3) and squa e sec ion sho s eel columns (SSC) (Table 4). The expe imen al p og am o es s on SP included i e di e en mo a (CM, DCM, DGMP, DGMV, and DRCM), and 45 specimens we e p oduced. Each se o h ee specimens used in hei he mal es s was used o ob ain be e eliabili y o esul s. Table 3. Expe imen al p og am on s eel pla e specimens. Mo a Designa ion Wi hou NS and MS Wi h NS and MS To al No. o Specimens LA Me hod IM Me hod LA Me hod IM Me hod CM 3 (*) (*) (*) 45 DCM 3 3 3 3 DGMP 3 3 3 3 DGMV 3 3 3 3 DRCM 3 3 (**) (**) (*) The comme cial solu ion was no modi ied, so he e was no need o es mo e han h ee specimens. (**) Since his mo a has he wo s esul s, i has no been es ed wi h he addi ion o silica mic o- and nanopa icles. Appl. Sci. 2022,12, 2093 5 o 20 Table 4. Expe imen al p og am on sho s eel columns. Di e en Types o Tes ed Columns Specimens Designa ion Numbe o Repe i ions To al No. o Specimens Columns wi hou passi e i e p o ec ion SSC1 2 12 SSC2 Columns coa ed wi h CM SSC3 2 SSC4 Column coa ed wi h DCM Wi hou MS and NS SSC5 2 SSC6 Wi h MS and NS SSC11 2 SSC14 Column coa ed wi h DGMP Wi hou MS and NS SSC7 2 SSC8 Wi h MS and NS SSC12 2 SSC13 Table 3p esen s he expe imen al p og am de ined o e alua e he in luence o he size o he agg ega es and he addi ion o silica mic o- and nanopa icles on he he mal pe o mance o he de eloped mo a s. The pe cen age o silica mic o- and nanopa icles we e he same and equal o 0.5% in weigh o binde o each one. All specimens we e exposed o high empe a u es on one side up o 900 ◦ C. Addi ionally, he expe imen al p og am o es s ca ied ou on 12 SSC unde i e condi ions included h ee di e en i e p o ec ion mo a s (CM, DCM, and DGMP). DGMV and o he s new ones will make pa o ano he u u e expe imen al campaign, in which di e en agg ega es/addi i es will be s udied. 2.3. P epa a ion o he Specimens The manu ac u ing p ocess, shape, and dimensions o he SP and moulds we e de ined o measu e he he mal g adien gene a ed be ween he inne su ace o he s eel pla e exposed o high empe a u es and he exposed su ace o he i e p o ec ion mo a . Thus, a sui able mould was designed and manu ac u ed o hese es s (Figu e 1). Appl. Sci. 2021, 11, x FOR PEER REVIEW 6 o 22 2.3. P epa a ion o he Specimens The manu ac u ing p ocess, shape, and dimensions o he SP and moulds we e de- ined o measu e he he mal g adien gene a ed be ween he inne su ace o he s eel pla e exposed o high empe a u es and he exposed su ace o he i e p o ec ion mo a . Thus, a sui able mould was designed and manu ac u ed o hese es s (Figu e 1). (a) (b) Figu e 1. Mould used in he manu ac u e o SP: (a) mould componen s; (b) mould assembly. This mould assigns he desi ed geome ic shape o he specimen, was easy o anspo and clean, was eusable o many expe imen al es s, and was easy o assemble and disassemble when conc e ing and emo ing he specimen. Du ing he ab ica ion o mo a s, a balance accu a e o 0.1 g , a g adua ed beake , Hoba N50 mixe wi h 5 L o capaci y and a s ainless-s eel lab spa ula we e used. The p ocedu e adop ed in he ab i- ca ion o mo a s was as ollows: 1. The aw ma e ials we e weighed and placed inside he mixe con aine . 2. Then, he mixe was pu in o ope a ion o 5 min a a slow speed (136 o a ions pe minu e). A he same ime, he co esponding amoun o wa e was added, wi h a cons an low a e o gua an ee he homogeneous addi ion o wa e in he whole mo - a . 3. A e his p ocedu e, he mo a was manually kneaded wi h a spa ula o emo e pa s o he mo a ha we e on he walls o he con aine and hus homogenize he mix u e, hen e u ning he con aine o he mixe o ano he 2 min. 4. The mo a was placed inside he mould (Figu e 2). In he p oduc ion o mo a s, he same p ocedu e was ollowed o ensu e ha he di e en p ope ies o he mo a s we e only dependen on hei composi ion. To mini- mize possible e ec s ha empe a u e and humidi y migh ha e on he p ope ies o each mo a composi ion, all mix u es o each composi ion we e manu ac u ed on he same day and placed in a oom wi h con olled en i onmen al condi ions. I is well known ha he mois u e con en g ea ly in luences he i e beha io o mo a s a ele a ed empe a- u es [39,40], in he same way as in he conc e es. (a) (b) (c) (d) Figu e 1. Mould used in he manu ac u e o SP: (a) mould componen s; (b) mould assembly. This mould assigns he desi ed geome ic shape o he specimen, was easy o anspo and clean, was eusable o many expe imen al es s, and was easy o assemble and disassemble when conc e ing and emo ing he specimen. Du ing he ab ica ion o mo a s, a balance accu a e o 0.1 g, a g adua ed beake , Hoba N50 mixe wi h 5 L Appl. Sci. 2022,12, 2093 6 o 20 o capaci y and a s ainless-s eel lab spa ula we e used. The p ocedu e adop ed in he ab ica ion o mo a s was as ollows: 1. The aw ma e ials we e weighed and placed inside he mixe con aine . 2. Then, he mixe was pu in o ope a ion o 5 min a a slow speed (136 o a ions pe minu e). A he same ime, he co esponding amoun o wa e was added, wi h a cons an low a e o gua an ee he homogeneous addi ion o wa e in he whole mo a . 3. A e his p ocedu e, he mo a was manually kneaded wi h a spa ula o emo e pa s o he mo a ha we e on he walls o he con aine and hus homogenize he mix u e, hen e u ning he con aine o he mixe o ano he 2 min. 4. The mo a was placed inside he mould (Figu e 2). Appl. Sci. 2021, 11, x FOR PEER REVIEW 7 o 22 (a) (b) (c) (d) Figu e 2. Manu ac u e o specimens: (a) Hoba N50 mixe ; (b) esh mo a in he mixe con aine ; (c) s eel pla e wi h he mocouples applied; (d) specimen in he p ocess o cu ing du ing he i s 48 h. Abou 48 h a e cas ing he SP in he moulds desc ibed abo e, hey we e demoulded and placed in he cu ing p ocess (Figu e 3a) o 28 days in he labo a o y en i onmen wi h con olled empe a u e (25 °C) and a ela i e humidi y (RH) o 55%. The specimens we e es ed wi h 6 mon hs o age. (a) (b) Figu e 3. (a) Specimens in he p ocess o cu ing; (b) specimen schema ic ep esen a ion and e- spec i e dimensions. The specimens comp ised a S355 s eel pla e wi h a squa e sec ion o 250 mm o edge and a hickness o 5 mm; and 10 mm hick i e p o ec ion mo a on one side o he s eel pla e (Figu e 3b). The empe a u e measu emen in he SP was ca ied ou by placing 4 ype K he mocouples. The he mocouples we e placed a di e en dep hs ac oss he spec- imen (Figu e 4). (a) (b) Figu e 4. Schema ic iew o he mocouples. (a) A-A’-A’’ c oss-sec ion in he middle o he specimen; (b) a angemen and designa ion o he mocouples. Wi h his dis ibu ion o he mocouples, i was possible o de e mine he he mal g adien be ween he su ace o he mo a exposed o high empe a u es (ESMHT— he - mocouple 3) and he unexposed su ace (USMHT— he mocouple 2), as well as he em- pe a u e on he inne su ace o he s eel pla e (ISSP— he mocouple 1) and i s ex e nal Figu e 2. Manu ac u e o specimens: ( a ) Hoba N50 mixe ; ( b ) esh mo a in he mixe con aine ; ( c ) s eel pla e wi h he mocouples applied; ( d ) specimen in he p ocess o cu ing du ing he i s 48 h. In he p oduc ion o mo a s, he same p ocedu e was ollowed o ensu e ha he di e en p ope ies o he mo a s we e only dependen on hei composi ion. To minimize possible e ec s ha empe a u e and humidi y migh ha e on he p ope ies o each mo a composi ion, all mix u es o each composi ion we e manu ac u ed on he same day and placed in a oom wi h con olled en i onmen al condi ions. I is well known ha he mois- u e con en g ea ly in luences he i e beha io o mo a s a ele a ed empe a u es [39,40], in he same way as in he conc e es. Abou 48 h a e cas ing he SP in he moulds desc ibed abo e, hey we e demoulded and placed in he cu ing p ocess (Figu e 3a) o 28 days in he labo a o y en i onmen wi h con olled empe a u e (25 ◦ C) and a ela i e humidi y (RH) o 55%. The specimens we e es ed wi h 6 mon hs o age. Appl. Sci. 2021, 11, x FOR PEER REVIEW 7 o 22 Figu e 2. Manu ac u e o specimens: (a) Hoba N50 mixe ; (b) esh mo a in he mixe con aine ; (c) s eel pla e wi h he mocouples applied; (d) specimen in he p ocess o cu ing du ing he i s 48 h. Abou 48 h a e cas ing he SP in he moulds desc ibed abo e, hey we e demoulded and placed in he cu ing p ocess (Figu e 3a) o 28 days in he labo a o y en i onmen wi h con olled empe a u e (25 °C) and a ela i e humidi y (RH) o 55%. The specimens we e es ed wi h 6 mon hs o age. (a) (b) Figu e 3. (a) Specimens in he p ocess o cu ing; (b) specimen schema ic ep esen a ion and e- spec i e dimensions. The specimens comp ised a S355 s eel pla e wi h a squa e sec ion o 250 mm o edge and a hickness o 5 mm; and 10 mm hick i e p o ec ion mo a on one side o he s eel pla e (Figu e 3b). The empe a u e measu emen in he SP was ca ied ou by placing 4 ype K he mocouples. The he mocouples we e placed a di e en dep hs ac oss he spec- imen (Figu e 4). (a) (b) Figu e 4. Schema ic iew o he mocouples. (a) A-A’-A’’ c oss-sec ion in he middle o he specimen; (b) a angemen and designa ion o he mocouples. Wi h his dis ibu ion o he mocouples, i was possible o de e mine he he mal g adien be ween he su ace o he mo a exposed o high empe a u es (ESMHT— he - mocouple 3) and he unexposed su ace (USMHT— he mocouple 2), as well as he em- pe a u e on he inne su ace o he s eel pla e (ISSP— he mocouple 1) and i s ex e nal su ace (ESSP— he mocouple 4). In Figu e 5, i is possible o iden i y he he mocouples on he specimen ollowing Figu e 4. Figu e 3. ( a ) Specimens in he p ocess o cu ing; ( b ) specimen schema ic ep esen a ion and espec i e dimensions. The specimens comp ised a S355 s eel pla e wi h a squa e sec ion o 250 mm o edge and a hickness o 5 mm; and 10 mm hick i e p o ec ion mo a on one side o he s eel pla e (Figu e 3b). The empe a u e measu emen in he SP was ca ied ou by placing Appl. Sci. 2022,12, 2093 7 o 20 4 ype K he mocouples. The he mocouples we e placed a di e en dep hs ac oss he specimen (Figu e 4). Appl. Sci. 2021, 11, x FOR PEER REVIEW 7 o 22 Figu e 2. Manu ac u e o specimens: (a) Hoba N50 mixe ; (b) esh mo a in he mixe con aine ; (c) s eel pla e wi h he mocouples applied; (d) specimen in he p ocess o cu ing du ing he i s 48 h. Abou 48 h a e cas ing he SP in he moulds desc ibed abo e, hey we e demoulded and placed in he cu ing p ocess (Figu e 3a) o 28 days in he labo a o y en i onmen wi h con olled empe a u e (25 °C) and a ela i e humidi y (RH) o 55%. The specimens we e es ed wi h 6 mon hs o age. (a) (b) Figu e 3. (a) Specimens in he p ocess o cu ing; (b) specimen schema ic ep esen a ion and e- spec i e dimensions. The specimens comp ised a S355 s eel pla e wi h a squa e sec ion o 250 mm o edge and a hickness o 5 mm; and 10 mm hick i e p o ec ion mo a on one side o he s eel pla e (Figu e 3b). The empe a u e measu emen in he SP was ca ied ou by placing 4 ype K he mocouples. The he mocouples we e placed a di e en dep hs ac oss he spec- imen (Figu e 4). (a) (b) Figu e 4. Schema ic iew o he mocouples. (a) A-A’-A’’ c oss-sec ion in he middle o he specimen; (b) a angemen and designa ion o he mocouples. Wi h his dis ibu ion o he mocouples, i was possible o de e mine he he mal g adien be ween he su ace o he mo a exposed o high empe a u es (ESMHT— he - mocouple 3) and he unexposed su ace (USMHT— he mocouple 2), as well as he em- pe a u e on he inne su ace o he s eel pla e (ISSP— he mocouple 1) and i s ex e nal su ace (ESSP— he mocouple 4). In Figu e 5, i is possible o iden i y he he mocouples on he specimen ollowing Figu e 4. Figu e 4. Schema ic iew o he mocouples. ( a ) A-A’-A” c oss-sec ion in he middle o he specimen; (b) a angemen and designa ion o he mocouples. Wi h his dis ibu ion o he mocouples, i was possible o de e mine he he mal g adien be ween he su ace o he mo a exposed o high empe a u es (ESMHT— he mocouple 3) and he unexposed su ace (USMHT— he mocouple 2), as well as he empe a u e on he inne su ace o he s eel pla e (ISSP— he mocouple 1) and i s ex e nal su ace (ESSP— he mocouple 4). In Figu e 5, i is possible o iden i y he he mocouples on he specimen ollowing Figu e 4. Appl. Sci. 2021, 11, x FOR PEER REVIEW 8 o 22 Figu e 5. Iden i ica ion o he mocouples, 1–4, on he specimen ollowing Figu e 4. Conce ning he SSCs es s, specimens we e de ined by a hollow squa e sec ion 150 × 150 × 8 mm, wi h a heigh o 1250 mm, and he s eel g ade was S355. A he column ends, i was cen e ed and welded a s eel pla e (sec ion 300 × 300 × 20 mm), as shown in Figu e 8. To e alua e he empe a u e e olu ion on he ex e nal su aces o he s eel columns du ing he es , 12 ype K he mocouples we e welded, equidis an om each o he on all he specimen’s su aces, applied in 3 g oups o 4 he mocouples a di e en heigh s. These e mocouples we e welded in he middle o he su aces o he s eel ubula columns. To gua an ee a cons an and uni o m mo a hickness o 20 mm along he s eel columns, a modula o mwo k was de eloped wi h he abili y o assign he desi ed geome ic shape- wi h easy assembly and disassembly while conc e ing he specimen. Figu e 6 depic s he loca ion o he h ee g oups o he mocouples and he di e en conc e ing s eps o he s eel columns. The specimens we e es ed a e cu ing o 6 mon hs. Figu e 5. Iden i ica ion o he mocouples, 1–4, on he specimen ollowing Figu e 4. Conce ning he SSCs es s, specimens we e de ined by a hollow squa e sec ion 150 ×150 ×8 mm, wi h a heigh o 1250 mm, and he s eel g ade was S355. A he column ends, i was cen e ed and welded a s eel pla e (sec ion 300 × 300 × 20 mm), as shown in Figu e 8. To e alua e he empe a u e e olu ion on he ex e nal su aces o he s eel columns du ing he es , 12 ype K he mocouples we e welded, equidis an om each o he on all he specimen’s su aces, applied in 3 g oups o 4 he mocouples a di e en heigh s. These e mocouples we e welded in he middle o he su aces o he s eel ubula columns. To gua an ee a cons an and uni o m mo a hickness o 20 mm along he s eel columns, a modula o mwo k was de eloped wi h he abili y o assign he desi ed geo- Appl. Sci. 2022,12, 2093 8 o 20 me ic shapewi h easy assembly and disassembly while conc e ing he specimen. Figu e 6 depic s he loca ion o he h ee g oups o he mocouples and he di e en conc e ing s eps o he s eel columns. The specimens we e es ed a e cu ing o 6 mon hs. Appl. Sci. 2021, 11, x FOR PEER REVIEW 9 o 22 (a) (b) (c) (d) Figu e 6. Dis ibu ion o he mocouples (a) and ab ica ion o specimens, p econc e ing (b), con- c e ing on he sho s eel columns (c), and conc e e specimen wi hou o mwo k (d). 2.4. Expe imen al Tes ing Sys em and P ocedu e The expe imen al es ing sys em (Figu e 7) used in he mal analysis o s eel pla es consis ed o a cylind ical o en wi h in e nal dimensions 400 mm in heigh and 250 mm in diame e , capable o eaching a maximum empe a u e o 1200 °C (a) and he espec i e o en con olle (b). A Da alogge TDS-530 was used as a da a acquisi ion sys em (c) o eco d he empe a u e eadings. Rega ding he es p ocedu e, a e sealing all he exis - ing unions and holes o he o en wi h ock wool, a 8 cm hick ock wool blanke wi h a ci cula opening o 210 mm in diame e was also placed on he op o he o en (e), which allows he passage o hea om he in e io o he o en o he specimen. Subsequen ly, he specimen (d) was placed on he op o he o en, i.e., on he ock wool blanke and cen ed wi h he ba ycen ic axis o he o en. Figu e 7. Expe imen al se up: (a) cylind ical o en(b) o en con olle (c) da a acquisi ion sys em(d) specimen(e) ock wool. In all es s, he specimens we e placed in a sui able posi ion o ensu e pe ec accom- moda ion wi h he ock wool and hus a oid hea losses be ween he specimen and he o en. The specimen was hea ed a a hea ing a e o 15 °C/minu e un il eaching he desi ed empe a u e le el (900 °C). Tempe a u es inside he specimen and he o en we e Figu e 6. Dis ibu ion o he mocouples ( a ) and ab ica ion o specimens, p econc e ing ( b ), conc e - ing on he sho s eel columns (c), and conc e e specimen wi hou o mwo k (d). 2.4. Expe imen al Tes ing Sys em and P ocedu e The expe imen al es ing sys em (Figu e 7) used in he mal analysis o s eel pla es consis ed o a cylind ical o en wi h in e nal dimensions 400 mm in heigh and 250 mm in diame e , capable o eaching a maximum empe a u e o 1200 ◦ C (a) and he espec i e o en con olle (b). A Da alogge TDS-530 was used as a da a acquisi ion sys em (c) o eco d he empe a u e eadings. Rega ding he es p ocedu e, a e sealing all he exis ing unions and holes o he o en wi h ock wool, a 8 cm hick ock wool blanke wi h a ci cula opening o 210 mm in diame e was also placed on he op o he o en (e), which allows he passage o hea om he in e io o he o en o he specimen. Subsequen ly, he specimen (d) was placed on he op o he o en, i.e., on he ock wool blanke and cen ed wi h he ba ycen ic axis o he o en. Appl. Sci. 2021, 11, x FOR PEER REVIEW 9 o 22 (a) (b) (c) (d) Figu e 6. Dis ibu ion o he mocouples (a) and ab ica ion o specimens, p econc e ing (b), con- c e ing on he sho s eel columns (c), and conc e e specimen wi hou o mwo k (d). 2.4. Expe imen al Tes ing Sys em and P ocedu e The expe imen al es ing sys em (Figu e 7) used in he mal analysis o s eel pla es consis ed o a cylind ical o en wi h in e nal dimensions 400 mm in heigh and 250 mm in diame e , capable o eaching a maximum empe a u e o 1200 °C (a) and he espec i e o en con olle (b). A Da alogge TDS-530 was used as a da a acquisi ion sys em (c) o eco d he empe a u e eadings. Rega ding he es p ocedu e, a e sealing all he exis - ing unions and holes o he o en wi h ock wool, a 8 cm hick ock wool blanke wi h a ci cula opening o 210 mm in diame e was also placed on he op o he o en (e), which allows he passage o hea om he in e io o he o en o he specimen. Subsequen ly, he specimen (d) was placed on he op o he o en, i.e., on he ock wool blanke and cen ed wi h he ba ycen ic axis o he o en. Figu e 7. Expe imen al se up: (a) cylind ical o en(b) o en con olle (c) da a acquisi ion sys em(d) specimen(e) ock wool. In all es s, he specimens we e placed in a sui able posi ion o ensu e pe ec accom- moda ion wi h he ock wool and hus a oid hea losses be ween he specimen and he o en. The specimen was hea ed a a hea ing a e o 15 °C/minu e un il eaching he desi ed empe a u e le el (900 °C). Tempe a u es inside he specimen and he o en we e Figu e 7. Expe imen al se up: ( a ) cylind ical o en ( b ) o en con olle ( c ) da a acquisi ion sys em (d) specimen (e) ock wool. Appl. Sci. 2022,12, 2093 9 o 20 In all es s, he specimens we e placed in a sui able posi ion o ensu e pe ec accom- moda ion wi h he ock wool and hus a oid hea losses be ween he specimen and he o en. The specimen was hea ed a a hea ing a e o 15 ◦ C/minu e un il eaching he desi ed empe a u e le el (900 ◦ C). Tempe a u es inside he specimen and he o en we e measu ed e e y 5 s. When he a ge empe a u e in he specimen was eached, i was main ained uni o m du ing 3 h and a e , he es was gi en as concluded. The expe imen al layou o he sho s eel columns (SSC) unde i e condi ions (Figu e 8) consis ed essen ially o a eac ion s eel ame (A) o apply he se iceabili y load on he specimen, a suppo s eel ame (B), a hyd aulic jack (C), and an elec ic u nace (H). Appl. Sci. 2021, 11, x FOR PEER REVIEW 10 o 22 measu ed e e y 5 s. When he a ge empe a u e in he specimen was eached, i was main ained uni o m du ing 3 h and a e , he es was gi en as concluded. The expe imen al layou o he sho s eel columns (SSC) unde i e condi ions (Fig- u e 8) consis ed essen ially o a eac ion s eel ame (A) o apply he se iceabili y load on he specimen, a suppo s eel ame (B), a hyd aulic jack (C), and an elec ic u nace (H). Figu e 8. Expe imen al sys em used in he labo a o y o es SSCS. The le e s in his igu e a e de- ined in he ollowing ex . This s eel ame was de ined by HEB 500 columns and a HEB 600 beam (A), wi h a s i ness capable o minimizing possible displacemen s o his s eel s uc u e du ing he es s. Addi ionally, a suppo 3D s eel ame consis ing o wo ames (B) wi h HEB 300 columns and HEB 400 beams accommoda e he es ing specimen o simila ac ual bound- a y condi ions. Rega ding he es equipmen , a 3 MN hyd aulic jack (C) and i s con olle (J), a 3 MN load cell (D), and a 1 MN load cell (E) we e used o measu ing he comp ession o ces. Ten linea a iable displacemen ansduce s we e used o displacemen s meas- u emen s (F), a Da alogge (G) o da a acquisi ion, and an elec ic u nace (H) o hea up he s eel columns (I). A hyd aulic jack con olled by a se o-con olled cen al was used, and a p eload o 50% o he design alue o he loadbea ing capaci y o he columns a ambien empe a- u e (ULS) was applied (727.8 kN) o simula e a se ice load on he specimen. A e s abi- lising his loading in he specimen, he u nace was swi ched on and he specimen hea ed acco ding o he empe a u e e olu ion es ablished by he ISO 834 s anda d i e cu e [41]. Figu e 8. Expe imen al sys em used in he labo a o y o es SSCS. The le e s in his igu e a e de ined in he ollowing ex . This s eel ame was de ined by HEB 500 columns and a HEB 600 beam (A), wi h a s i ness capable o minimizing possible displacemen s o his s eel s uc u e du ing he es s. Addi ionally, a suppo 3D s eel ame consis ing o wo ames (B) wi h HEB 300 columns and HEB 400 beams accommoda e he es ing specimen o simila ac ual bounda y condi ions. Rega ding he es equipmen , a 3 MN hyd aulic jack (C) and i s con olle (J), a 3 MN load cell (D), and a 1 MN load cell (E) we e used o measu ing he comp ession o ces. Ten linea a iable displacemen ansduce s we e used o displace- men s measu emen s (F), a Da alogge (G) o da a acquisi ion, and an elec ic u nace (H) o hea up he s eel columns (I). Appl. Sci. 2022,12, 2093 16 o 20 Table 8. A e age empe a u e alue ob ained on he specimens o SSC. Di e en Types o Tes ed Columns Specimens Designa ion A e age Tempe a u e o Specimens (◦C) C i ical Tempe a u e (◦C) A e age Failu e Time Fi e Resis ance Ra ing 15 30 60 90 (Minu es) (Failu e Time) (Minu es) Columns wi hou passi e i e p o ec ion SSC1 525 - - - 560 ◦C (17 min) 17 R15 SSC2 572 - - - 617 ◦C (17 min) Columns coa ed wi h CM SSC3 78 111 351 - 560 ◦C (85 min) 81 R60 SSC4 77 108 360 - 531 ◦C (77 min) Column coa ed wi h DCM Wi hou MS and NS SSC5 96 220 465 - 566 ◦C (82 min) 83 R60 SSC6 103 242 481 - 585 ◦C (84 min) Wi h MS and NS SSC11 96 193 447 - 582 ◦C (88 min) 90 R90 SSC14 92 186 425 557 559 ◦C (91 min) Column coa ed wi h DGMP Wi hou MS and NS SSC7 79 115 341 535 576 ◦C (98 min) 97 R90 SSC8 75 119 342 545 572 ◦C (95 min) Wi h MS and NS SSC12 76 116 328 516 566 ◦C (102 min) 100 R90 SSC13 76 114 328 525 564 ◦C (98 min) Appl. Sci. 2021, 11, x FOR PEER REVIEW 17 o 22 Figu e 13. E olu ion o empe a u e in he specimens o SSC as a unc ion o ime. Table 8 shows he a e age empe a u e alues acqui ed in he specimens a e 15, 30, 60, and 90 min and he a e age empe a u e alues o he ailu e ins an s o each speci- men. The c i ical design empe a u e calcula ed acco ding o EN 1993-1-2: 2005 [41] o his sho s eel column was 586.7°C. In Figu e 12, he es ed SSC2 ailed a 17 min, SSC4 a 77 min, SSC6 a 84 min, SSC8 a 95 min, SSC12 a 102 min, and SSC14 a 91 min, co esponding o he empe a u e o 617, 531, 585, 572, 566, and 559°C, espec i ely (see also Table 8). In Figu e 13 and Table 8, i can be seen ha he comme cial mo a has a mo e e ec i e he mal p o ec ion o lowe empe a u es ( he highes delay in he empe a u e ise a he beginning o he es ). How- e e , o empe a u es highe han 400°C, i s he mal capaci y ends o dec ease due o he deg ada ion o he mo a ( he highes empe a u e ise a e a he ending o he es ). Figu e 14 depic s he specimen be o e and a e being es ed. Rega ding he ins abil- i y modes o he s eel columns, local ins abili y was obse ed despi e he column being a class 1 c oss-sec ion unde i e condi ions. Figu e 14. Pho os o he specimens o SSC be o e and a e es ed, as an example. 0 200 400 600 800 1000 1200 010 20 30 40 50 60 70 80 90 100 110 Tempe a u e (°C) Time (minu es) ISO 834 Fu nace Tempe a u e TSSC1,SSC2 TSSC3,SSC4 TSSC5,SSC6 TSSC7,SSC8 TSSC12,SSC13 TSSC11,SSC14 Figu e 14. Pho os o he specimens o SSC be o e and a e es ed, as an example. The esul s om Table 8clea ly show ha he applica ion o mo a s wo ks as a good he mal ba ie o i e, since columns wi hou passi e i e p o ec ion ailed a e 17 min o es ing, whe eas he p o ec ed columns ailed on a e age, beyond 81 min. Fu he mo e, he esul s also show ha he he mal p o ec ion o mo a s de eloped in he labo a o y was mo e e icien han ha p o ided by he comme cial mo a s. Finally, i appea s ha he in oduc ion o he NS and MS sligh ly imp o ed he he mal pe o mance o he mo a s de eloped in he labo a o y. Table 8shows ha he specimen wi hou passi e i e p o ec ion p esen ed a i e esis ance a ing (FRR) o 15 min (R15), and he p o ec ed specimens wi h he CM allowed a FRR o R60. Conce ning he he mal pe o mance o he mo a s de eloped in he labo a o y, i was ound ha he specimens p o ec ed wi h he DCM had a FRR o R60. When NS and MS we e added o i s composi ion, a FRR inc eased o R90. The specimens p o ec ed wi h he DGMP, wi h and wi hou NS and MS, p esen ed a FRR o R90. The indings esul s ob ained om he sho s eel columns p o ec ed wi h he di e en mo a s ypes we e in ag eemen wi h he ones ob ained in he es s ca ied ou on he p o ec ed s eel pla es, which makes hese explo a o y es s use ul o p elimina y selec ion o p omising i e p o ec ion ma e ials. Appl. Sci. 2022,12, 2093 17 o 20 4. Conclusions The objec i e o his wo k was o de elop gypsum o cemen -based mo a s o passi e i e p o ec ion and o e alua e he in luence o agg ega e size and he addi ion o silica mic o- and nanopa icles on i s he mal pe o mance. The he mal pe o mance o hese mo a s in sho s eel columns unde a comp ession se ice load and subjec ed o high empe a u es was assessed. The ollowing conclusions can be d awn: • The u nace, he dimensions o he specimens, and he es p ocedu e adop ed in he es s a high empe a u es allowed an adequa e he mal exposu e o he specimens. I allowed he e alua ion o he he mal pe o mance o he a ious mo a s es ed. • Some mo a s de eloped in he labo a o y (DCM, DGMP, and DGMV) ha e be e he mal pe o mance when compa ed wi h he bes comme cial solu ion es ed (CM). Fu he mo e, in his se o mo a s wi hou nano- and mic opa icles o silica, he mo a s wi h e miculi e in hei cons i u ion we e hose wi h he bes he mal pe o mance. • Mos mo a s wi h aw ma e ial milled h ough he Los Angeles me hod had be e he mal pe o mance han mo a s de eloped wi h aw ma e ial p ocessed h ough he Indus ial Mill me hod. Howe e , i nano- and mic opa icles o silica a e added in hei composi ion, he mo a s de eloped wi h aw ma e ial ob ained h ough he Indus ial Mill me hod may ha e a sligh ly supe io he mal pe o mance. • The addi ion o nano- and mic opa icles o silica imp o es he insula ing capaci y o he mo a s. • O e all, he esul s demons a e ha he educ ion in g ain size o he aw ma e- ials used (pe li e and e miculi e) did no bene i he he mal pe o mance o he es ed composi ions. • Rega ding he c acking o he mo a s, i was concluded ha pe li e (DGMP) con- ibu es o i s low alue. I was also concluded ha , in gene al e ms, he addi ion o NS and MS ends o inc ease he c acking deg ee o he de eloped composi ions. • The composi ions ha use gypsum as a binde (DGMP and DGMV) had he bes he - mal insula ion capaci y. Unde he es ed condi ions, i was ound ha 10 mm o mo a coa ing was su icien o o m an e icien he mal ba ie , educing he ISSP empe a- u e by app oxima ely 70% o he empe a u e eco ded inside he o en (900 ◦C). • The he mal p o ec ion le el o columns wi h he mo a de eloped in he labo a o y wi h he bes o e all he mal pe o mance (DGMP wi h nano- and mic opa icles o silica) was 19% mo e e icien han he comme cial solu ion and inc eases by 5.9 imes he i e esis ance o an unp o ec ed sho s eel column. These esul s demons a ed he ac ual impac ha he applica ion o such mo a s can ha e as passi e i e p o ec ion o s eels s uc u es. Bea ing in mind he expe imen al indings ob ained in his esea ch s udy, u he expe imen al es s on sho s eel columns wi h he de eloped mo a s and new ones by using di e en addi i es as well as wi h di e en loading condi ions will be ca ied ou in he nea u u e. Au ho Con ibu ions: Concep ualiza ion, H.C. and A.S. (Aldina San iago); me hodology, H.C.; so wa e, A.S. (Aldina San iago); alida ion, L.L., L.D. and A.S. (Ashkan Shahbazian); o mal analysis, H.C.; in es iga ion, H.C.; esou ces, A.S. (Aldina San iago); da a cu a ion, A.S. (Aldina San iago); w i ing—o iginal d a p epa a ion, H.C.; w i ing— e iew and edi ing, L.L.; isualiza ion, H.C.; supe ision, H.C.; p ojec adminis a ion, A.S. (Aldina San iago); unding acquisi ion, A.S. (Aldina San iago). All au ho s ha e ead and ag eed o he published e sion o he manusc ip . Funding: This esea ch was unded by he Po uguese Founda ion o Science and Technology (FCT), g an numbe PTDC/ECI-EGC/31850/2017. Ins i u ional Re iew Boa d S a emen : No applicable. In o med Consen S a emen : No applicable. Appl. Sci. 2022,12, 2093 18 o 20 Acknowledgmen s: The au ho s g a e ully acknowledge he Po uguese Founda ion o Science and Technology (FCT) o i s suppo unde he amewo k o esea ch p ojec PTDC/ECI-EGC/31850/2017 (NANOFIRE—The mal and Mechanical beha iou o Nano Cemen s and hei applica ion in s eel cons uc ion as i e p o ec ion) and also o he Uni e si y o Coimb a (UC) o hei suppo unde he Scien i ic Employmen S imulus P og amme gi en o he i s au ho , as well as o he Eu opean Regional De elopmen Fund, he Eu opean Social Fund, and Eu opean S uc u al and In es men Funds. This wo k was also inanced by FEDER unds h ough he Compe i i i y Fac o s Ope a ional P og amme—COMPETE and by na ional unds h ough FCT wi hin he scope o he p ojec POCI- 01-0145-FEDER-007633 and h ough he Regional Ope a ional P og amme CENTRO2020 wi hin he scope o he p ojec CENTRO-01-0145-FEDER-000006. Con lic s o In e es : The au ho s decla e no con lic o in e es . Abb e ia ions CM Comme cial passi e p o ec ion solu ion used as a e e ence mo a CPPS Comme cial passi e p o ec ion solu ion DCM De eloped cemen i ious mo a DGMP De eloped gypsum mo a wi h pe li e DGMV De eloped gypsum mo a wi h e miculi e DRCM De eloped e ac o y cemen i ious mo a EC Expanded clay EP Expanded pe li e ERC Ele oland e ac o y cemen ESMHT Exposed su ace o he mo a o high empe a u es ESSP Ex e nal su ace o he s eel pla e o he es specimen EV Expanded e miculi e GP Gypsum powde IGN Comme cial passi e p o ec ion solu ion 1 IM Indus ial mill me hod IRC Isidac 40 e ac o y cemen ISSP Inne su ace o he s eel pla e o he es specimen LA Los Angeles me hod MS Mic opa icles o silica NS Nanopa icles o silica PC Po land cemen CEM II/B-L 32.5 PP Polyp opylene ibe s PP/B Polyp opylene ibe s cemen a io in weigh % RC Re ac o y cemen RH Rela i e humidi y SD S anda d de ia ion SP S eel pla e SS Silica sand SSC Sho s eel columns T Tempe a u e Time TH The mocouple TRC Topeca M40 e ac o y cemen USMHT Unexposed su ace o he mo a o high empe a u es VER Comme cial passi e p o ec ion solu ion 2 W Wa e W/B Wa e binde (cemen o gypsum) a io in weigh % Re e ences 1. 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